Synthetic electrical musical system



Aug. 29, 1933. EREMEEFF SYNTHETIC ELECTRICAL MUSICAL SYSTEM Filed June4, 1932 5 Sheets-Sheet l I. EREMEEFF Aug. 29, 1933.

SYNTHETIC ELECTRICAL MUSICAL SYSTEM Filed June 4, 1952 5 Sheets-Sheet 2\lllll K II 1933. I. EREMEEFF 1,924,713

SYNTHETIC ELECTRICAL MUSICAL SYSTEM Filed June 4, 1932 5 Sheets-Sheet 5s INVENTOR.

Aug. 29, 1933. EREMEEFF 1,924,713

SYNTHETIC ELECTRICAL MUSICAL SYSTEM Filed June 4, 1952 5 Sheets-Sheet 4i 1 1 l l 1 Filed June 4, 1932 5 Sheets-Sheet 5 Eng -32 $82 80$ 3% 93d23 $3 w; Mus

mmu

J an

on N www INVENTOR.

Patented Aug. 29, 1933 UNITED STATES PATENT OFFICE SYNTHETIC ELECTRICALMUSICAL SYSTEM 6 Claims.

My invention relates to a system consisting of one or more synchronouslycoupled electrical musical instruments, each of which is capable ofproducing electrically tones of predetermined pitch, predeterminedsynthetic quality, and predetermined tonal expressions, the latter beingproduced by various keying means, with provision, if desired, fortremolo and a continuing diminishing of the tones after the keying hasbeen discontinued. Each instrument of this system is provided withearphone attachments for the purpose of silent practise, and is alsoprovided with individual couplings for a common line to sound emittingdevices. This system also provides controlling and viewing means foraiding a conductor to direct the operators of the said instruments.

It is an object of my invention to devise a system which utilizespulsating electric currents whose frequencies correspond to thefrequencies of the tones of a musical scale. Such pulsating electriccurrents are either produced in each individual instrument of thissystem or are produced in distant central generators which sup plypulsating electric current to the individual instruments. Eachindividual instrument is provided with means for combining atpredetermined intensities, a pulsating electric current, whosefrequency, which I shall call fundamental", corresponds to that of apredetermined musical tone, with predetermined numbers of pulsatingelectric currents whose frequencies are multiples of said fundamental,and which I shall call harmonics, or with predetermined numbers of itssub-harmonics as well as its harmonies. Provision is also made forcombining currents of fundamental frequency with their harmonics,sub-harmonics, and frequencies which are fractions of the firstharmonic, corresponding to the tones of a musical scale.

Another object of my invention is to devise a system of syntheticelectrical musical instruments whose principal features are not togenerate frequencies, as all musical instruments do, but to mix alreadygenerated frequencies according to my theory, also including what isgenerally known as the Helmholtz theory, in which the fundamental, orlowest, frequency is combined with a predetermined number of itsharmonies which are, of course, its exact multiples.

This latter theory, however, is in many cases unpractical, such as when,for example, a fundamental of very high frequency is combined withharmonics of higher frequency, which are mostly inaudible.

The main features of my invention are the mixing of fundamentals (whichare not of the usual lowest frequency of a combination but offrequencies of the highest intensity) with their harmonics, with theirsub-harmonics, and with fractional frequencies of the first harmonic ofeach fundamental, at different predetermined intensities which arereadjustable during said mixing without its discontinuation, keying ofrapid response, and diminishing and tremolo effects. Another feature isthe application of common line currents to different instruments for thepurpose of perfect tuning and for maintaining the phase occurrence ofeach pulsating electric current in all the instruments in such a mannerthat the superposed currents of the same frequencies of the individualinstruments will combine correctly without destroying each other orproducing beat tones.

The nature and objects of my invention will be more fully understoodfrom the following specification and claims, reference being had to theaccompanying drawings, in which:

Fig. 1 represents a view of a system of synthetic electrical musicalinstruments which include their own electrical generators.

Fig. 2 shows a system in which a distant central generator supplies aplurality of instruments.

Figs. 3 and 4 represent detail views of what is shown in Fig. 1,illustrating individual electrical musical instruments comprisinggenerating, mixing, keying, etc. units.

Fig. 5 is a diagrammatic view of synthetic electrical musicalinstruments which are supplied from a distant common generator.

Fig. 6 represents details of what is shown in Figs. 2 and 5,illustrating synthetic electrical musical instruments being suppliedfrom a distant common generator.

Figs. 7, 8, and 9 represent oscillograms depicting keying effects andtremolo.

Figs. 10, 11, 12, 13, and 14 are diagrams illustrating the theory ofsynthetic combinations which my electrical musical instruments are madeto perform, and which are included among the objects of my invention.

In Fig. 1, 1, 2, 3, 4, 5, and 6 represent musical instruments which havemeans to generate, mix, and control by key, pulsating electric currentswhich are transmitted by the output lines as 7, 8, 9 to the common line10 into the amplifying and filtering system 11, which is optional, andinto the sound emitting device 12. The control cabinet 13 lsoperated bya conductor for the purpose of switching on and on and combining theoutputs of lines 7, 8, 9, etc. in the common circuit 10 at differentdegrees of intensity. The oscillograph 14, with taps for each of theoutput lines at 7, 8, 9, permits the conductor stationed at cabinet 13to analyze the wave forms of the pulsating electric currents produced byeach instrument such as 1, 2, 3, 4, 5, 6. While otherwise similar to theinstruments 1, 2, 3, 4, etc., the instruments 5 and 6 are dual, whichmay, perhaps, be more convenient at times.

The power line 15 supplies alternating electric current of suitablefrequency to the synchronous motors in the instruments 1 to 6, etc. forthe purpose of keeping them in tune, as will be explained later.Switches such as 16 and earphones as 1'! are provided for eachinstrument for the purpose of allowing each operator to practise uponhis instrument without disturbing the others, the switches providing forconnection to the common circuit when so desired. Details ofconstruction of these instruments are to be found in Figs. 3 and 4.

In Fig. 3, 18 represents a synchronous motor which drives a plurality ofshafts as designated by C, C#, D, Di, E, F, Ft, G, Gt, A, All, and B,whose speed is proportional to the frequencies of the correspondingtones of a musical scale. The said shafts are driven by motor 18 withthe aid of an endless uniform, non-slipping belt, or belts. Fig. 4 showsthe same shafts driven by worms as 19 and worm gears as 20, in which asmall increase in speed is obtained by changing the diametral pitch insaid worms and gears without changing their actual diameters. In view ofthe fact that the art of generating pulsating electric currents iswell-known, I will not repeat a means for this purpose unless inexplanation of mixing or keying means, and throughout this specificationI will use means of generating which are most suitable for my purpose,although these are not the objects of my invention.

, The non-magnetic grilles 21, 22, 23, etc., which are made to support aplurality of iron and permanent magnet core magnets with coils againstco-operative phonic wheels on shafts C, Ct, D, etc. slide toward andaway from the phonic wheels by graduated movement with the aid of thehandles such as 24, 25, etc., for the purpose of engaging said magnetssuch as 26, with their co-operative phonic wheels such as 2'1, forgenerating pulsating electric current in the coils of said magnets, theintensity of said current increasing as the gaps between the phonicwheels and the magnetsin the grilles decrease.

The line 28 connects in series the magnet 26 of grille 21, the magnet30' of grille 22, and the magnet 31 of grille 23. The variableresistance 32 permits of increase in the e of pulsating electric currentat slight pressure upon key 33. 34 represents a device for releasing key33 at a predetermined speed for producing a continued diminishing in theintensity of said pulsating electric current to its original value. Theoperation of these parts will be more fully described in followingpages. Line 35 connects the magnets 36, 37, 38 of grilles 21, 22, 23,respectivetensity of the pulsating electric current depending upon thepressure of said conductor on plate 39, and the passage of pulsatingelectric current increasing as the pressure of said conductor causes anincrease in the area of contact with plate 39. The grilles 21, 22, 23,etc. are also controlled by foot movement, if desired, with the aid ofthe pedals 43, 44, etc.

The grilles 21, 22', 23, etc., of Fig. 4 are similar to the grilles 21,22, 23, etc. of Fig. 3, there being only a single vertical bar forsupporting magnets in Fig. 4 instead of several as in Fig. 3, due tolack of space. The number of teeth of the phonic wheels, the wiring ofthe magnets, and the movements of the grilles in both Fig. 3 and Fig. 4will be explained in following pages. Also, complete explanation ofdesigns and operation can be found in my co-pending application SerialNumber 544,821, filed June 16, 1931.

The movements of the handles and pedals which control the grilles aregraduated and callbrated for the purpose of correctly setting thegrilles for generation of currents of predetermined intensities.

Returning to Fig. 2, the instruments 1', 2', 3', 4, 5', 6', etc.represent the types which are supplied with pulsating electric currentfrom a distant common generator, and have mixing and keying means forproducing such combinations as outlined in Figs. 16, 11, 12, 13, and 14.The line 45 is provided with current for driving suitable motors fortremolo and diminishing effects, which will be described later, morecomplete detail views being shown in Figs. 5 and 6. In Fig. 2, theinstruments 5' and 6' are dual, and the remaining parts with similarsymbols to those of Fig. 1, represent the same parts as shown in bothfigures, such as 10, 11, 12, 13, 14, 16, and 17.

In Fig. 5 the distant common generator 46, which is shown in detail inFig. 6, consists of a plurality of generator units which producepulsating electric current at suitable intensities in order thatamplification is optional. As already mentioned, the generation ofpulsating electric currents is not new, and therefore I will show onlythe necessary means which are provided for this purpose. Generation, forexample, can be obtained by the application of vacuum tubes, phonicwheel or magneto methods, for generating pulsating electric current,electrical pick-ups driven by grooves, or commutators with differentnumbers of segments running at different velocities. The selection ofsuitable generators such as 46, depends on the output of its units atpredetermined frequencies, and also depends on phase occurrence. Thelatter is so regulated as to avoid overlapping which produces beat toneeffects. However, a novel feature in the art of generating pulsatingelectric currents can be found in the form of gearing illustratedas 19and 20 in Fig. 4, which, as stated, makes possible the driving of aplurality of shafts with any fractional ratios between each other.

47 and 48 of Fig. 6 represent a plurality of commutators which produceand transmit pulsating electric currents of predetermined frequenciesfrom the battery 49 into the supply lines 50, each of said lines havingits own predetermined number of cycles. For producing in a soundemitting device such as 12 tones of a musical scale of, for example,seven octaves, twelve compound commutators as 47, 48 are required, sinceeach compound commutator produces seven frequencies which are multiplesof each other, or,

speaking in terms of music, octaves. The same can be obtained by usingtwelve members such as 20, each having a groove as 51 and a pick-up as52, producing a frequency from each member. 53 represents a frequencymultiplier of any conventional type, whose design is not the object ofmy invention. If each pick-up as 52 produces a frequency of for example16 cycles 'per second, the frequency multiplier 53 will produce incircuits 54 six frequencies which are multiples of each other, inaddition to the frequency generated in the circuit 52, 55 may be avacuum tube oscillator or a gaseous diode oscillator as shown,

using, for example, a rectifying tube whose size depends on the amountof output current required, the circuit of which is shown in thediagram. Such a unit generates currents of considerable strength, whichmakes amplification optional. I

53" represents a multiplying frequency converter similar to 53, and maybe of any conventional type, the construction of which is not among theobjects of my invention. 56 represents one of a plurality of vacuum tubeoscillators similar to 55 which produces currents whose frequenciescorrespond to the frequencies of the tones of a musical scale in theform of octaves beginning with the lowest and ending at the highest.

Say, for example, there'are twelve tubes, the first producing afrequency of 16.1! which corresponds to On of a musical scale, alsosupplying the circuits' 50 with six additional frequencies whichcorrespond respectively to Co, Cl, Ca. C1, C5, of a musical scale, withthe aid of a frequency multiplier such as 53', the next tube producing afrequency of 17.13 which corresponds to C# 1 of a musical scale, alsosupplying circuits 50with additional frequencies corresponding to C#0,C#l, C#z, etc., with theaid of a frequency multiplier-similar to 53',and so forth, thus producing frequencies which-correspond to thefrequencies of an entire musical scale. The number of octaves doesnotnecessarily have to be limited to seven, and as shown in the graphs ofFigs. 10, 11, 13, and 14, there may be as many as for example, ten.

In Fig. 5, the two instruments 1' and 2' are shown having connection tothe common circuits 50 as in Fig. 2, the details of which areillustrated in Fig. 6.- The non-magnetic sliding panels 21", 22", 23",etc., have graduated movements as have the grilles 21, 22, 23, etc.shown in Figs. 3 and 4.

These panels slide to and fro in the channels such as 57, independent ofeach other, and are provided with rods as 58, 59, 60, 61, 62, etc. whichcarry on their ends suitable coils, each of which is supplied with apulsating electric current of predetermined frequency from a distantcommon generator as 46. Opposite to said coils are placedreceiving-coils as 58', 59', 60, 51', 62', etc., which individuallyreceive pulsating electric currents from the coils on the ends of thegraduated rods 58, 59, 60, etc. at predetermined intensities dependingon the adjustable gaps between .said transmitting and receiving coils.The gaps between said coils are adjusted by individually sliding eachpanel as 21" toward and away from the coil as 58' or by adjusting eachindividual rod as 58 in panel 21" without moving said Each of the keysas 63, 33, and the plates such as 39, has a bank of transmitting andreceiving coils as 64, or resistances as 65, or other mediums suchas 66,which permit of the transmission'of pulsating electric current from thepower circuits connecting to the circuits 50 into the key circuits suchas 64", 65', 66', etc. The construction of the mediums as 66 is notamong the objects of my invention. Key 63 does not employ resistances asdoes the key 33 for the purpose of increasing and decreasing theintensity of the pulsating electric current since all the receivingcoils as 58', 59', 60', 61', etc., are securely mounted on the bracket67 and are lifted upward and aligned with the transmitting coils on therods 58,v 59, 60, 61, etc., when key 63, is depressed to the limit. Thereceiving elements of the keys 33 and 33' are stationary and thetransmitting elements are commonly or individually adjusted by thepanels 21", 22",23", etc., or by the rods as 68, 68', 68", etc. The bankof transmitting and receiving elements 66 is mounted rigidly and saidelements may be of any suitable design as long as they performtransmission of current from one circuit to another. The bank 65comprises variable resistances which are suitably distributed throughouttheir length, and are adjusted, as said, by individual and by commonmeans.

For example, all of the panels as 21", 22", 23", etc., may be broughtforward to a definite zero position. The graduated rods 58, 68, or 69,are then adjusted for transmission of,. for example pulsating electriccurrent of 50% intensity, from circuits 50, by, for example, lines 70and 71, of the key circuit 65. By sliding the panels as 21" toward thebanks of receiving elements, all of the rods in said panels will beautomatically advanced, thus increasing the intensity of the pulsatingelectric current in the circuits of the receiving elements of the keycircuits as 64, 65, 66, etc.

Each bank, such as 64, is merely a collector of currents from itsco-operative transmitting elements, receiving complex pulsating electriccurrent which is the combination of a plurality of simple pulsatingelectric currents of predetermined frequencies and adjustableintensities. The intensities can always be varied during thecombination, as weiiasduring the keying action, by the rods as 58, 59,60, 61, 62, etc., and by the panels as 21", 22", 23", etc., as stated.Details concerning the wiring of the banks and the mixing of currents ofvarious intensities individually and commonly will be given in followingpages.

The instrument 2' of Fig. 5 is similar to instrument 1'. However, theinstrument 2 shows different keying, such as the arrangement of platesas 39 and conductors as 42, which were explained in regard to Fig. 3.The wiring of the arrangement 39, 42, as in Fig. 5, shows applicationfor multiple arrangements providing for many keys in place of the singlearrangement of Fig. 3. It can be seen that all the receiving units as 72are wired in parallel to a common circuit '73 which connects to one sideof the primaries of transformers 74 and '15, while the lines 76 and 77,leading from two diil'erent banks, are connected at will by conductorssuch as 42, which have flexible connections as 78, in order to completethe circuit.

The output of the banks, whichareselectively controlled by theconductors 42, is combined in the common circuit 41, the intensity-miwhose current is increased or decreasedby a potentiometer as 80 with avolume control pedal as 81.

Current from the coil 82 is transmitted to the movable coil 83 andcircuit 8 at an intensity which depends on the position of the coils 82and 83.

any moving coil 83 into coil 82 with the aid of the device 84 at apredetermined fraction of time. controlled by pedal 85, variation ofcurrent is produced such as represented in Fig. 9 by the oscillographcurve'B, which shows two forms of intensity variations, fast and slow.This periodical variation of intensity of the current in circuit 8produces a tremolo eifect when said current is converted into soundenergy. The intensity of said current is regulated by potentiometer 86in the cabinet of the conductor. The output of banks as 64, 65, 68, etc.in instrument 1' is also combined in the common circuit 41, the volumecontrol pedal 81' and potentiometer varying the intensity of the currentin coil 82'. Transmission of current from cell 82' into cell 83' andinto circuit 7 is made by device 84' which works without a motor, unlikethe device 84. Variation of current in circuit 7 is obtained by themoving of coil 83' into coil 82 by means of the plunger 87 inside thecoil 88, which has connection to oscillatory currents of differentsuitable frequencies supplied from the distant common generator 46 bylines 89. The tremolo pedal selectively connects coil 88 to differenttaps on the lines 89 for permitting plunger 87 to vibrate at differentspeeds depending on the number of cycles of that particular line towhich the switch of pedal 85' is connected.

Continuous diminishing eifeots are obtained as follows: motor unit 90,whose speed is controlled by the diminisher pedal 91, drives roller 92at any suitable speed in the direction indicated by arrow. Slidingweight 34 moves by friction in the direction indicated by arrow, andpushes pin 93 of key 63 until said key resumes a normal restingposition, and bank 84 with bracket 87 is lowered. No transmission ofcurrent from the transmitting coils on rods 58, 59, etc. to receivingcoils as 58', 59', etc., occurs since the gap between them is increased.

Sliding weight 34 is then held stationary, with slippage on the roller92, which continues to revolve at a speed controlled by diminisher pedal91. When key 83 is depressed to the limit, pin 93 pushes weight 34forward against the friction of roller 92 in a direction reverse to thatshown by arrow, and bracket 67, which is hinged to key 63, is lifted,steadying itself by means of the sliding pin 94 in the stationarysupport 95. Current is transmitted from the transmitting elements. as onrods 58, 59, etc. to the receiving'elements as 58', 59', etc. as long askey 83 is held depressed. When key 63 is released, said key will notreturn to its resting place immediately, but will return at a speedwhich depends on the position of the diminisher pedal 91 and on thespeed of the roller 92. Said roller picks up sliding weight 34 (whichslips on roller 92 during the time. of depression of key 63) and carriessaid weight by friction in the direction indicated by arrow at a speed'already regulated by pedal 91, until said key resumes its restingposition after a certain length of time. This diminishing actiongradually discontinues the reception of current from said transmittingelements, producing a gradual fading effect when said current isconverted into sound energy.

Instrument 2' of Fig. 5 is alsopro ded with a diminishing means for thekey arrangements 39, 42, which is similar to that of the keys 63, 33,33', etc. of instrument 1'. Details of means for producing diminishingeflects as in the case or instrument 2' of Fig. 5.can be foimd in Fig.8. The diminishing mechanism asapplied to instrument 2' of Fig. 5 issimilarto thatofinstru ment 1'; however, as in Fig. 6, a resistance 98is placed upon the weight 34 over an insulating plate in such a mannerthat the stationary contact point 97 rests on resistance 96 in such away that current is not permitted to pass from line 73' into 73" unlessconductor 42 is placed on 39 at a predetermined degree of pressure,providedthat the stopp device 98 does not permit key 40to be depressed.

The reason for current not being permitted to pass, is that the point 97rests on resistance 98 in such a position that no direct transmissionfrom line 73' to 73" takes place. If there were transmission. soundwould be heard in the output. The resistance of 98 at the resting pointof 97 is very high, and the resistance 96, aftersliding in the directionindicated by arrow, is gradually lowered as the pointer 97 takesdifferent positions on said resistance. Where there is no resistance,current from line 73'. easily passes into line 73". This resistance hasbeendescribed, and is used for producing diminishing effects, and is inuse only when it moves in the direction opposite to that indicated byarrow, since direct connection is made between line 73' and plate 39 andconductor 42 to line 73". In other words, when the finger touches theplate 39, (when lever 98 permits of rocking key 40), current from 73passes either through the finger or the moving resistance. When thefinger leaves the plate, current passes only through the alreadylessened resistance of 96.

This arrangement provides complete finger,

touch, without having to move a heavy mass for transmitting currentsinto the circuit 41. For producing the diminishingv effects, stop 98 isplaced in the position of (a) permitting theconductor 42 to transmitcurrent and to depress key 40, at the same time moving resistance 96 inthe direction indicated by arrow, while contact point 97 is stationary.Current from line 73' is-transmitted either through the lessenedresistance 98 or by conductor 42, into circuit 73", but when conductor42 leaves plate 39, resistance 96 is moved in the opposite directionfrom that indicated by arrow, with the aid of roller 92, at a speedwhich is controlled by a diminisher'pedal as 91 in Fig. 5. Said resistorcontinues to move back until contact point 97 has resumed its originalposition.

It is to be understood that the arrangenfent for producing diminishingeifects as shown can be applied to all of the keys of each instrument,-

and certain parts, such as sliding weight. 34,

have been shown in simplified form for the sake of explanation. Similarfeatures for producing diminishing eifects have been disclosed in mycopending patent application Serial Number 486,391, flied October 4,1930, and allowed May- 24, 1932.

Figs. 7, 8, and A of Fig. 9 illustrate the results of various keyingeflects which can be obtained by such arrangements'as 32,- 33, 39, 40,and 42, of Figs. 3, 5, and 6. A of Fig. 7 shows the eii'ects of slowincrease and rapid decrease in intensity of current obtained by thevarious keying means mentioned above, while B of Fig. 7 illustratesrapid increase and slow decrease of current, depending upon the variouspressures and contacts given to the keys. If the current represented byA of. Fig. 7 is converted into sound energy, the 10 decibels asindicated would produce a tone about as loud as a whisper, gradwhich issuitable in an auditorium. From 70 decibels. the current represented byA again decreases to about 10 decibels; however. the decrease being muchfaster than the increase, as can readily be seen in A of Fig. 7. Therapid decrease of A to zero from 10 decibels is produced eitherby.releasing the key as 33, shown in Fig. 6, rapidly; or disconnectingthe conductor 42 from the plate 39, also shown in Fig. 6. B of Fig. 7shows the effects of rapid increase in intensity from about 10 decibelsto 70 decibels with a slow decrease again to 10 decibels and then tonothing. 1 In Fig. 8, A illustrates a uniform increase and decrease from10 decibels to about 70 decibels and again to 10 decibels. B of Fig. 8shows a sudden increase from 10 to 70 decibels, held for a time at 70decibels, and again suddenly decreased to 10 decibels. Such effects canbe obtained by a short quick touch of the conductor 42, of Fig. 6, uponthe plate 39, where it is held at a uniform intensity, and then suddenlylifted from it.

In Fig. 9, A shows the effects of various pressures on a key such as 33,or on plate 39 by a conductor as 42, shown in Fig. 6, varying from zeroto 10 decibels, held uniform for a short period, increased to and helduniformly at 20 decibels, gradually increased and held at '70 decibels,then dropping gradually to about 10 decibels. held uniform for a time,then increased to about 40 decibels, and again dropping to 10 decibelsand returning to the zero point. ThlS illustrates the pliability ofcontrolling the pulsating electric currents by means of my variouskeying systems.

B of Fig. 9 represents tremolo effects, the rapid and slow variationsbeing produced by the tremolo pedals as and 85 of Fig. 5, the numbers indecibels, of course, representing the variations in both cases. For thesake of explanation, the decibel figures were cited. These are not to betaken scrupulously.

Figs. 10, 11, 12, 13, and 14 illustrate the art of combining oscillatorymatter, either in the form of electricity or sound. In view of the factthat I am describing electrical musical instruments, I will explain inelectrical form, the musical scales whose frequencies correspond to thefrequencies of my electrical currents. Fig. 10 represents a musicalscale ranging from 16 cycles to approximately 10 octaves above Frepresents a fundamental of 16 cycles, with its first harmonic of 32cycles, its'second harmonic of 64 cycles, its third harmonic of 129cycles, and so forth. The fundamental F has a high intensity, and whencombined with its first, second, third, etc. harmonics, said harmonicshaving predetermined intensities, complex pulsating electric currentresulting from such combination will be obtained. When such current isconverted, without distortion, into sound energy, the quality of thesound will have characteristics depending on the combination. Bychanging the number of harmonics, and by changing the intensity of thefundamental and the harmonics, a new quality of sound will be heard froma sound emitting device without changing the pitch, which will be thatof the fundamental provided that it continues to have the highestintensity. As previously stated, this is the generally accepted theoryof producing different qualities of sound. However, if the fundamentalhas a very high frequency, such as F of Fig. 10, and some of itsharmonics are above the range of audibility, musical sounds cannot beproduced as well as in the case of lower frequency fundamentals. F and1'" illustrate the number of harmonics available for fundamentals of 24cycles and 488 cycles respectively. The numbers placed below thekeyboard represent the frequency numbers of those keys directly abovethem. To those familiar with the frequencies of musical tones, it isknown that the cycle numbers are generally carried at least to twodecimals. For simplicity I will disregard these decimals, such as 18.17,for which I will merely use 16.

As already stated, my invention is made to conform with suchcombinations as illustrated in Fig. 10, as well as with my owncombinations as shown in Figs. 11, 12, 13, and 14. In Fig. 11,fundamental F has ten harmonics, fundamental F has nine harmonics, butfundamental F has nine partials. five of which are harmonics, and theremaining four are "sub-harmonics". Fundamental F has ten partials, two'exact harmonics, and eight subharmonics. It can be seen that the numberof partials of the various fundamentals in Fig. 11 are practically thesame, while in Fig. 10, the higher the frequency of the fundamental, thefewer are its partials.

In Fig. 12, each fundamental, as F F and F, has eleven partials whichcorrespond to the tones of a musical scale. For example, the partials offundamental F are: partial no. 1, frequency 17, (17.13 to be exact)partial no. 2, frequency 18, partial no. 3, frequency 19, and so forth.Likewise, since fundamental F has a frequency of 17, its first partialwill have a frequency of 18, its second partial frequency 19, its thirdpartial frequency 20, and so forth. These partials are fractions of thefirst exact harmonic of each fundamental, the first harmonic, of coursebeing a multiple of the fundamental always. In other words, the firstpartial of each fundamental is the first fraction of the first harmonicof the fundamental.

In Fig. 13, the fundamental F, frequency 16, has eleven partials, 17,18, 19, 20, 21, 22, 24, 25, 2'7, 28, and 30, as well as ten exactharmonics. Altogether, fundamental F has twenty-one partials, the firstmentioned eleven partials being fractions of the first harmonic which isdesignated by frequency 32, which, of course, is an exact multiple offundamental F, frequency 16.

In Fig. 14, as in Fig. 13, the fundamental F is combined with tenpartials which are exact multiples of said fundamental, and elevenpartials which are fractions of the first harmonic, frequency 32.However, in addition, Fig. 14 shows the partials designated by thenumberals I, II, III, IV, V, and VI, which are so-called in-betweenharmonics of the fundamental F, frequency 16. For example, partial Irepresents an exact thirdmultiple of the fundamental F, and has afrequency of 48; partial II represents an exact fifth multiple offundamental F, and has a frequency of 81; partial III represents anexact sixth multiple, frequency 96; partial IV represents an exact ninthmultiple of the fundamental, and has a frequency of 145; partial Vrepresents a tenth multiple, frequency 162; and partial VI represents amultiple by twelve times, frequency 194. Of course, there may be as manyniore of such multiples of the fundamental as desired. Due to the factthat the entire decimal of each frequency number is not given, aspreviously explained, the frequency numbers of the various partials arenot, then, exact multiples. For example, while the tenth partial offundamental F, frequency 16, is given as frequency 162, this is reallyan exact multiple of the entire number 16.17, the remaining of Ffraction accounting for the additional 2" in 162.

It is to be noted that the frequencies of all fractions, harmonics, andsub-harmonics mentioned, can be found in a musical scale, and can beproduced electrically from currents whose frequencies correspond to thefrequencies of a musical scale. It is also to be understood that theconventional musical scale of tones and half-tones can be applied withquarter-tones, or scales which may be called metric, of uniform ratiosof strictly multiplying frequencies can also be utilized.

For the production of musical tones by systems such as illustrated inFigs. 3 and 4, their synthesis is shown in Fig. 10. In Fig. 3, thegrille 21 is brought to the position so that the gaps baween the phonicwheels and their co-operative magnets permit of the production ofpulsating electric current of predetermined intensity, for example,100%. Shaft C of Fig. 3, rotates for example, 16.17 times per second.Phonic wheel 27, having one tooth on its periphery, generates oneimpulse per revolution, producing 16.17 impulses per second at anintensity of 100%. This is illustrated in Fig. 10 by fundamental Ffrequency 16.17. Grilles 22, 23, etc. are brought into position forgenerating pulsating electric current of 100% intensity. Phonic wheel27' has, for example, two teeth, and naturally produces 32 (fractionomited) impulses per second as illustrated by harmonic 1 of F in Fig.10. Phonic wheel 27" of Fig. 3, has, for example, four teeth on itsperiphery, producing 64 impulses per second, which is illustrated inFig. 10 as harmonic 2 Additional phonic wheels with eight teeth, sixteenteeth, etc., produce the harmonics '3, 4, 5, etc. of F in Fig. 10. Themagnets 26, 30, 31, etc. are coupled by the common circuit 28, andpulsating electric current, which can be represented by the combinationof fundamental F and a predetermined selective number of its harmonics,all of 100% intensity, is transmitted to circuit 41 with the aid of thekeying means 33 or 39, 42. By lowering grille 22 to a predeterminedposition, the intensity of the current in magnet 30 is lessened to, forexample, producing a change in the resulting combined current, since theintensity of the fundamental is 100%, the intensity of its firstharmonic is 50%, that of the second harmonic is 100%, and so forth. Formore alteration in the resultant current, grille 21 may be lowered to95% intensity, grille 22 may be lowered to 15%, grille 23 to etc. sothat the current in circuit 28, which will be complex, of course, willbe the combination of fundamental F frequency 16, key of 0-1; at anintensity of 95%, with harmonic 1, frequency 32, key of Co, at anintensity of 15%, harmonic 2, frequency 64, key of C1, at an intensityof 60%. If said grilles are, for example, adjusted to positionsproducing the intensities mentioned, all of the magnets and theco-operative phonic wheels of grille 21, for example, will generatecurrent of 95% intensity, and the magnets and phonic wheels of grille 22will generate current of 15% intensity, etc.

If the magnet 36, shown in Fig. 3, on shaft B, were placed, for example,on shaft C, which makes 16.17 revolutions per second, the frequency ofthe current generated would be 258, since the phonic wheel co-operatingwith magnet 36 has 16 teeth, as do all of the phonic wheels in theposition of the beginning of the fifth octave. However, magnet 36 isreally located at shaft B which revolves faster than shaft C, making30.52 revolutions per second. Multiplying this by 16, which representsthe number of teeth on the phonic wheel co-operating with magnet 36. thecurrent generated has a frequency of 488, which is designated in Fig. 11as the frequency of F The magnet 37 of Fig. 3 co-operates with a phonicwheel having 32 teeth, generating current of 15% intensity, frequency976, corresponding to the tone one octave higher than that representedby F and this is designated in Fig. 11 as harmonic no. 1.

Magnet 38 co-operates with a phonic wheel of eight teeth, since it ismadeto generate the first sub-harmonic of F as 1' of Fig. 11, whosefrequency is one octave lower than that of 1''. being 244, and whoseintensity is 60%, due to the adjustment of grille 23. The complexpulsating electric current in circuit 36 of Fig. 3 will be thecombination of the fundamental current of magnet 36 at an intensity of95%, frequency 488. with the first harmonic current from magnet 37 at anintensity of 15%, frequency 976, and the sub-harmonic current frommagnet 38 at an intensity of 60%, frequency 244.

The following, or fourth grille, aftergriile 23, would be provided forthe second harmonic of F the fifth grille would be provided for thesecond sub-harmonic, as 2' of Fig. 11, and so forth. Each grille isadjusted for different intensities without static or without causingdisconnection in the circuits.

The wiring diagram of Fig. 4 shows the magnet of grille 21 and shaft Ccoupled with the magnet of grille 22' and shaft C#, which are in turncoupled with the magnet of grille 23' and shaft D, and so forth on allthe shafts respectively. Each phonic wheel co-operating with saidmagnets has one tooth, the entire row of coupled magnets and theirphonic wheels producing, for example, frequencies of 16 to 30 cycles,due to the fact that each shaft revolves faster than the precedent onein accordance with the frequencies of a musical scale. For example,shaft C revolves 16.17 times per second, shaft C# revolves 17.13 timesper second, shaft D revolves 18.15 times per second, shaft D# revolves19.22 times per second, etc. All the magnets are coupled by line 28' andwill produce what is illustrated in Fig. 14 as the fractions of thefirst harmonic of the fundamental F. Magnet 30' co-operates with aphonic wheel with two teeth, producing a frequency which is twice ashigh as the fundamental, which would be represented by the harmonic no.1 of fundamental F in Fig. 14. Magnet 31' cooperates with a phonic wheelof three teeth, producing a frequenccy which is three times as high asF, designated in Fig. 14 by the numeral I. It can be said that the nextmagnet following 31' co-operates with a phonic wheel of four teeth,producing a frequency which is four times as high as the fundamental F,shown in Fig. 14 as harmonic no. 2, while the next magnet, 00-

operating with a phonic wheel of five teeth, produces a frequency whichis five times as high as F, shown in Fig. 14 by numeral II, and soforth.

The magnets connected in the circuit 28" are placed in the samerespective grilles as are the magnets coupled by line 28'. The currentsgenerated by the magnets of line 28" are a trifle higher in frequency,by as much as the ratio between, for example 16.17 and 17.13. Theintensities of the currents of all the magnets of each grille as 21',22', 23, 1, I, 2, II, etc., are adjusted to predetermined degreessimultaneously.

For obtaining combinations such as illustrated in Figs. 10 to 14, thesynthetic electrical musical instruments of my inventon operate asfollows:

for combining a fundamental as F in Fig. 10, with a predetermined numberof its harmonics, at different predetermined degrees of intensity, rod58, shown in Fig. 5, has a transmitting coil which is connected to lineZ of circuit 50, and delivers pulsating electric current at a frequencyof 16.17 cycles per second. The rods 59, 60, 61, etc. are so adjusted,by being pulled forward, that the gaps between the transmitting and thereceiving coils are greatly increased, in order that no transmissionoccurs excepting between the coil 58 and the coil of rod 58, when key 63is depressed. At this time, a current of 16.17 cycles is permitted topass into the circuit 64. Then the rods 59, 60, 61, etc. are pushedtoward their co-operative receiving coils to predetermined degrees forthe additional transmission of other currents with predeterminedintensities. The coil of rod 59, for example, connects to line Y whichcarries currents of 32.33 cycles, the coil of rod connects to line X,which carries currents of 64.66 cycles. the coil of rod 61 connects toline W, which carries currents of 129 cycles, and so forth.

By depressing the key such as 63, complex pulsating electric current,which is the combination of a fundamental of 16.17 cycles, with apredetermined selective number of its harmonics, each said harmonichaving a predetermined intensity, is transmitted into a sound emittingdevice as 12, given tremolo or diminishing effects if desired, and thendiscontinued without static or circuit breaking disturbances. By varyingthe number of harmonics which are combined with said fundamental, byadjustment of rods 58 to 62, etc., and by changing the intensities ofsaid harmonics, unlimited synthetic combinations can be made, thusproducing a variety of different tone qualities when said complexcurrent is converted into sound energy.

Fig. 11 has been described in regard to the synthesis of fundamentalswith harmonics and subharmonics. If key 33, of Fig. 5, produces currentcomprising of a fundamental frequency 488, shown as F in Fig. 11, coilof rod 68 connects to for example, line P, which carries current of 488cycles. The coil of rod 68', which controls connection of the firstharmonic, is connected to line 0, which carries current of 976 cycles.This is represented in Fig. 11 as the first harmonic of fundamental FThe coil of the rod 68 is provided for the first sub-harmonic, andconnects to line N, which carries current of 244 cycles, which, ofcourse, is one half as high as that of the fundamental, whose frequencyis 488. The coil of rod 68" connects to line M which carries current of1953 cycles, for production of the second harmonic of fundamental Frepresented in Fig. 11 as harmonic no. 2. The next coil of the next rodconnects to its own line for the second sub-harmonic of the fundamental,and so forth.

If the key 63 of Fig. 5 is depressed for producing a fundamentalfrequency of 16.17 cycles, shown in Fig. 14 as F, which is combined withits harmonics, sub-harmonics, and other partials, the wiring of thecoils on the rods 58, 59,

60, 61, etc., will be as follows: the coil of rod 58 will connect toline Z, for frequency 16.17, coil of rod 59 connects to line Z for thefirst fractional partial, which is, for example, frequency 17.13, coilof rod 60 connects to line Z for the second fractional partial which is,for example, frequency 18.18, and so forth, until all of the partialswhich are fractions of the first harmonic of fundamental F are connectedin, for example, eleven lines, in the same order. The

twelfth rod, for example, connects its coil to line Y, which carriescurrent of 32.33 cycles, for the first harmonic of the fundamental, thethirteenth rod connecting its coil to line Y, which carries currents of48.44 cycles, and which is three times as high as the fundamental, infrequency. This frequency is designated in Fig. 14 as the multiple I.The coil of the fourteenth rod would be connected to line X, whichcarries currents of frequency which is four times as high as that of thefundamental, and is indicated in Fig. 14 as the second harmonic of thefundamental F. Certain of the lines used in describing the connectionsin key 63, are used in other keys.

Having thus described my invention, what I claim as new and useful is:

1. In a synthetic electrical musical system comprising a centralizeddistant generator which supplies pulsating electric current to aplurality of independent electrical musical instruments, means forproducing a plurality of pulsating electric currents of uniform waveforms, whose frequencies correspond to the frequencies of the tones ofan audible musical range, said pulsating electric currents havingdefinite phase relationships between each other to avoid overlapping,which produces additional frequencies, means for supplying the mixers ofa plurality of said independent electrical musical instruments with aplurality of pulsating electric currents, each of said currents beingpredeterminedly utilized in each of said instruments as a fundamental,as the fractions of the first harmonics of corresponding fundamentals,and as the harmonics, sub-harmonics, and multiples of correspondingfundamentals.

2. In a synthetic electrical musical system comprising a plurality ofindependent electrical musical instruments and a distant centralizedgenerator which supplies a plurality of pulsating electric currents tothe mixer and banks of each of said electrical musical instruments,means for manually and automatically producing in the output circuit ofeach of said electrical musical instruments a predetermined compoundpulsating electric current which is selectively received from the banksof the mixer of each of said electrical musical instruments atpredetermined intensities and at predetermined fractions of time, andmeans for predeterminedly varying the intensities of said compoundpulsating electric currents in said output circuits at predeterminedvariable fractions of time.

3. In a system for producing music electrically by a plurality ofelectrical musical instruments which are fed by a distant commongenerator, means for selectively and individually combining in thecircuits of the individual banks of the mixers of said instruments, apredetermined number of pulsating electric currents, each said currenthaving predetermined intensity and predetermined frequency, forproducing in the circuit of each of said banks a complex pulsatingelectric current of predetermined wave form, the number of saidpulsating electric currents, and their predetermined intensities andpredetermined frequencies being predeterminedly and individuallyvariable during said selective combining of said pulsating electriccurrents, for the purpose of individually altering the wave forms ofsaid complex pulsating electric currents in the circuits of said mixerbanks, means for selectively and commonly combining the pulsatingelectric currents in the circuits of said mixer banks into complexpulsating electric currents of predetermined wave forms, and said meansvarying the number, intensities, and frequencies of the individualpulsating electric currents in the circuits of said mixer banks for thepurpose of commonly altering the wave forms of said complex pulsatingelectric currents.

4. In a synthetic electrical musical system comprising a plurality ofsynchronously coupled electrical musical instruments, centralized meansfor individually and commonly controlling the intensities of the outputsof said electrical musical instruments, with provision for individuallyvisualizing the wave forms of the outputs of said electrical musicalinstruments.

5. In a synthetic electrical musical system, a plurality ofsynchronously coupled electrical musical instruments, each of saidinstruments comprising a generator, a mixer, a keyboard, and diminisherand tremolo controls, each of said instruments having means to generatea plurality of pulsating electric currents of predetermined intensities,the frequencies of said currents corresponding to the frequencies of thetones of an audible musical range, graduated hand and foot operatedmeans to combine a predetermined number of selective generated pulsatingelectric currents of predetermined fundamental frequencies andpredetermined intensities with a predetermined number of theirco-operative selective pulsating electric currents at differentpredetermined variable intensities, the frequencies of said pulsatingelectric currents corresponding to the harmonies, the sub-harmonics, themultiples, and the divisions of the first harmonics of theirco-operative fundamental frequency pulsating electric currents, manuallyoperated means for passing the resultant complex pulsating electriccurrents, which are the selective combinations of said fundamentalfrequency pulsating electric currents and predetermined numbers of theirco-operative pulsating electric currents, into the output circuit ofeach said instrument, each said resultant complex pulsating electriccurrent passing into said output circuit at predetermined variableintensity and at predetermined variable fractions of time, automaticmeans for the diminishing passage of said resultant complex pulsatingelectric currents after the operation of said manually operated meanshas been discontinued, and means for producing tremolo effects bypredeterminedly varying the intensity of the compound pulsating electriccurrent in the output of each said instrument at predetermined variablefractions of time, when said compound pulsating electric current isconverted into sound energy.

6. A synthetic electrical musical system coniprising a plurality ofindependent electrical musical instruments, each of said instrumentsbeing capable of individually producing musical tones and chords ofpredetermined synthetic musical quality, means for supplying saidplurality of instruments with a predetermined number of pulsatingelectric currents from a common centralized generator, said generatorproducing said pulsating electric currents at predetermined intensities,which makes amplification optional, at predetermined frequencies, saidfrequencies corresponding to the frequencies of the tones of a musicalscale, and at definite phase occurrences relative to each other,graduated hand and foot operated means for independently and selectivelytransmitting into a predetermined keying circuit a pulsating electriccurrent of predetermined fundamental frequency and a predeterminedselective number of pulsating electric currents whose frequenciescorrespond to the harmonics, sub-harmonics, multiples, and fractions ofthe first harmonic of said fundamental frequency pulsating electriccurrent, each of said currents having predetermined intensity which isvariable during transmission of pulsating electric current, means forcombining said transmitted pulsating electric currents in a keyingcircuit which is provided for said fundamental frequency pulsatingelectric current, manual means for predeter- 195 minedly passing aresultant complex pulsating electric current into the output circuit ofeach of said individual electrical musical instruments at variableintensities and at variable fractions of time, automatic means forproducing a diminishing passage of each said resultant complex pulsatingelectric current when operation of said manual means has beendiscontinued, means for varying the intensity of the compound pulsatingelectric current in the output circuit of each of 110 said electricalmusical instruments per predetermined variable fraction of time,individual guiding means for private performance of each of saidelectrical musical instruments, centralized means for selectivelyviewing the wave forms of the compound pulsating electric current in theoutput circuit of each of said electrical musical instruments, andselective centralized means for combining the compound pulsatingelectric currents from the output circuits of said electrical musicalinstruments at predetermined intensities, said combined compoundpulsating electric currents later being converted into sound energy.

IVAN EREMEEFF.

